diff options
Diffstat (limited to 'crypto/src/math/ec/custom/sec/SecT233Field.cs')
| -rw-r--r-- | crypto/src/math/ec/custom/sec/SecT233Field.cs | 243 |
1 files changed, 243 insertions, 0 deletions
diff --git a/crypto/src/math/ec/custom/sec/SecT233Field.cs b/crypto/src/math/ec/custom/sec/SecT233Field.cs new file mode 100644 index 000000000..165fadbf3 --- /dev/null +++ b/crypto/src/math/ec/custom/sec/SecT233Field.cs @@ -0,0 +1,243 @@ +using System; +using System.Diagnostics; + +using Org.BouncyCastle.Math.Raw; + +namespace Org.BouncyCastle.Math.EC.Custom.Sec +{ + internal class SecT233Field + { + private const ulong M41 = ulong.MaxValue >> 23; + private const ulong M59 = ulong.MaxValue >> 5; + + public static void Add(ulong[] x, ulong[] y, ulong[] z) + { + z[0] = x[0] ^ y[0]; + z[1] = x[1] ^ y[1]; + z[2] = x[2] ^ y[2]; + z[3] = x[3] ^ y[3]; + } + + public static void AddExt(ulong[] xx, ulong[] yy, ulong[] zz) + { + zz[0] = xx[0] ^ yy[0]; + zz[1] = xx[1] ^ yy[1]; + zz[2] = xx[2] ^ yy[2]; + zz[3] = xx[3] ^ yy[3]; + zz[4] = xx[4] ^ yy[4]; + zz[5] = xx[5] ^ yy[5]; + zz[6] = xx[6] ^ yy[6]; + zz[7] = xx[7] ^ yy[7]; + } + + public static void AddOne(ulong[] x, ulong[] z) + { + z[0] = x[0] ^ 1UL; + z[1] = x[1]; + z[2] = x[2]; + z[3] = x[3]; + } + + public static ulong[] FromBigInteger(BigInteger x) + { + ulong[] z = Nat256.FromBigInteger64(x); + Reduce23(z, 0); + return z; + } + + public static void Multiply(ulong[] x, ulong[] y, ulong[] z) + { + ulong[] tt = Nat256.CreateExt64(); + ImplMultiply(x, y, tt); + Reduce(tt, z); + } + + public static void MultiplyAddToExt(ulong[] x, ulong[] y, ulong[] zz) + { + ulong[] tt = Nat256.CreateExt64(); + ImplMultiply(x, y, tt); + AddExt(zz, tt, zz); + } + + public static void Reduce(ulong[] xx, ulong[] z) + { + ulong x0 = xx[0], x1 = xx[1], x2 = xx[2], x3 = xx[3]; + ulong x4 = xx[4], x5 = xx[5], x6 = xx[6], x7 = xx[7]; + + x3 ^= (x7 << 23); + x4 ^= (x7 >> 41) ^ (x7 << 33); + x5 ^= (x7 >> 31); + + x2 ^= (x6 << 23); + x3 ^= (x6 >> 41) ^ (x6 << 33); + x4 ^= (x6 >> 31); + + x1 ^= (x5 << 23); + x2 ^= (x5 >> 41) ^ (x5 << 33); + x3 ^= (x5 >> 31); + + x0 ^= (x4 << 23); + x1 ^= (x4 >> 41) ^ (x4 << 33); + x2 ^= (x4 >> 31); + + ulong t = x3 >> 41; + z[0] = x0 ^ t; + z[1] = x1 ^ (t << 10); + z[2] = x2; + z[3] = x3 & M41; + } + + public static void Reduce23(ulong[] z, int zOff) + { + ulong z3 = z[zOff + 3], t = z3 >> 41; + z[zOff ] ^= t; + z[zOff + 1] ^= (t << 10); + z[zOff + 3] = z3 & M41; + } + + public static void Square(ulong[] x, ulong[] z) + { + ulong[] tt = Nat256.CreateExt64(); + ImplSquare(x, tt); + Reduce(tt, z); + } + + public static void SquareAddToExt(ulong[] x, ulong[] zz) + { + ulong[] tt = Nat256.CreateExt64(); + ImplSquare(x, tt); + AddExt(zz, tt, zz); + } + + public static void SquareN(ulong[] x, int n, ulong[] z) + { + Debug.Assert(n > 0); + + ulong[] tt = Nat256.CreateExt64(); + ImplSquare(x, tt); + Reduce(tt, z); + + while (--n > 0) + { + ImplSquare(z, tt); + Reduce(tt, z); + } + } + + protected static void ImplCompactExt(ulong[] zz) + { + ulong z0 = zz[0], z1 = zz[1], z2 = zz[2], z3 = zz[3], z4 = zz[4], z5 = zz[5], z6 = zz[6], z7 = zz[7]; + zz[0] = z0 ^ (z1 << 59); + zz[1] = (z1 >> 5) ^ (z2 << 54); + zz[2] = (z2 >> 10) ^ (z3 << 49); + zz[3] = (z3 >> 15) ^ (z4 << 44); + zz[4] = (z4 >> 20) ^ (z5 << 39); + zz[5] = (z5 >> 25) ^ (z6 << 34); + zz[6] = (z6 >> 30) ^ (z7 << 29); + zz[7] = (z7 >> 35); + } + + protected static void ImplExpand(ulong[] x, ulong[] z) + { + ulong x0 = x[0], x1 = x[1], x2 = x[2], x3 = x[3]; + z[0] = x0 & M59; + z[1] = ((x0 >> 59) ^ (x1 << 5)) & M59; + z[2] = ((x1 >> 54) ^ (x2 << 10)) & M59; + z[3] = ((x2 >> 49) ^ (x3 << 15)); + } + + protected static void ImplMultiply(ulong[] x, ulong[] y, ulong[] zz) + { + /* + * "Two-level seven-way recursion" as described in "Batch binary Edwards", Daniel J. Bernstein. + */ + + ulong[] f = new ulong[4], g = new ulong[4]; + ImplExpand(x, f); + ImplExpand(y, g); + + ImplMulwAcc(f[0], g[0], zz, 0); + ImplMulwAcc(f[1], g[1], zz, 1); + ImplMulwAcc(f[2], g[2], zz, 2); + ImplMulwAcc(f[3], g[3], zz, 3); + + // U *= (1 - t^n) + for (int i = 5; i > 0; --i) + { + zz[i] ^= zz[i - 1]; + } + + ImplMulwAcc(f[0] ^ f[1], g[0] ^ g[1], zz, 1); + ImplMulwAcc(f[2] ^ f[3], g[2] ^ g[3], zz, 3); + + // V *= (1 - t^2n) + for (int i = 7; i > 1; --i) + { + zz[i] ^= zz[i - 2]; + } + + // Double-length recursion + { + ulong c0 = f[0] ^ f[2], c1 = f[1] ^ f[3]; + ulong d0 = g[0] ^ g[2], d1 = g[1] ^ g[3]; + ImplMulwAcc(c0 ^ c1, d0 ^ d1, zz, 3); + ulong[] t = new ulong[3]; + ImplMulwAcc(c0, d0, t, 0); + ImplMulwAcc(c1, d1, t, 1); + ulong t0 = t[0], t1 = t[1], t2 = t[2]; + zz[2] ^= t0; + zz[3] ^= t0 ^ t1; + zz[4] ^= t2 ^ t1; + zz[5] ^= t2; + } + + ImplCompactExt(zz); + } + + protected static void ImplMulwAcc(ulong x, ulong y, ulong[] z, int zOff) + { + Debug.Assert(x >> 59 == 0); + Debug.Assert(y >> 59 == 0); + + ulong[] u = new ulong[8]; + // u[0] = 0; + u[1] = y; + u[2] = u[1] << 1; + u[3] = u[2] ^ y; + u[4] = u[2] << 1; + u[5] = u[4] ^ y; + u[6] = u[3] << 1; + u[7] = u[6] ^ y; + + uint j = (uint)x; + ulong g, h = 0, l = u[j & 7] + ^ (u[(j >> 3) & 7] << 3); + int k = 54; + do + { + j = (uint)(x >> k); + g = u[j & 7] + ^ u[(j >> 3) & 7] << 3; + l ^= (g << k); + h ^= (g >> -k); + } + while ((k -= 6) > 0); + + Debug.Assert(h >> 53 == 0); + + z[zOff ] ^= l & M59; + z[zOff + 1] ^= (l >> 59) ^ (h << 5); + } + + protected static void ImplSquare(ulong[] x, ulong[] zz) + { + Interleave.Expand64To128(x[0], zz, 0); + Interleave.Expand64To128(x[1], zz, 2); + Interleave.Expand64To128(x[2], zz, 4); + + ulong x3 = x[3]; + zz[6] = Interleave.Expand32to64((uint)x3); + zz[7] = Interleave.Expand16to32((uint)(x3 >> 32)); + } + } +} |